RU2539362C2 - Signal receiving method and device considering network loading assessment - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: group of inventions relates to communication equipment and can be used in wireless communication systems. Methods and devices for correction of quantisation errors at reception of a signal based on assessment of network loading include decisions for preservation of serviceability of mobile communication in low-noise environment and with considerable interference. As per Version 1, a data channel is amplified in comparison to other signals based on network loading during periods of relatively low network usage. Dynamic modification of power level of data channel serves for elimination of quantisation errors, but not actual noise level that is not considerable in low-noise environment.

EFFECT: reliability required for high degree of suppression of inconsiderable signals and preservation of data channel quality.

26 cl, 10 dwg

Description

A priority

This application claims the priority of the same applicant according to pending US application No. 12 / 698,901, filed February 2, 2010 with the same name, which is incorporated herein by reference in its entirety.

Copyright

Part of the description of this patent document contains material that is subject to copyright protection. Copyright owners do not object to the facsimile reproduction of any part of a patent document or description of a patent as shown in patent documents or records of the Patent and Trademark Office, but retain all copyright in any other case.

FIELD OF THE INVENTION

The present invention generally relates to the field of wireless communications and data networks. In particular, in one exemplary aspect, the present invention is directed to methods and devices for controlling signal reception based on network load estimates.

State of the art

In telecommunication networks, the term “orthogonality” refers to systems, processes, signal transmission, effects, etc. that exhibit the required exceptional properties. Orthogonality properties have significant applications in multiple access communication schemes. Consider a composite signal composed of several orthogonal signal components. Ideally, the receiver can extract the desired signal from the composite signal and suppress other orthogonal component signals. In this example, each of the orthogonal signal components is a removable “interference”.

For example, in systems based on CDMA (Code Division Multiple Access), complex sequences of orthogonal “spreading codes” are used to distinguish between all data and control channels. A CDMA signal can be divided into several component channels, ideally without mutual interference (interference) between the component channels (i.e., inter-channel interference or ICI (inter-channel interference)).

In contrast to receiving unwanted orthogonal signals, real noise is “non-orthogonal” and does not exhibit simple exceptional properties. For example, real noise includes elements such as nearby systems that cause interference, thermal noise, transmission phenomena, and the like. In contrast to the transmission of orthogonal signals, real noise is largely unpredictable and cannot be ruled out. In general, real noise should be corrected using error correction methods or have little power compared to signal transmit power.

In conventional wireless reception, the radio frequency part “converts” and translates the received radio frequency vibrations into digital form for the purpose of subsequent demodulation and / or processing. Most circuits for the RF part carry out the signal conversion steps before the demodulation and / or processing steps. In addition, the radio frequency part is usually constructed on the basis of computational tools with a fixed decimal point for cost and complexity reasons (i.e., a fixed number of characters is used for operations).

Unfortunately, limitations to the practical implementation of circuits during normal operation can create artifacts. For example, in a low noise environment, unwanted orthogonal signals can have significantly higher transmit power than the desired signal. These unwanted orthogonal signals will have a dominant effect on signal conversion operations. As described in greater detail below, such conditions can occur when the mobile device is very close to a lightly loaded base station (or femtocell). After unwanted orthogonal signals (such as pilot channels, broadcast channels, etc.) have been eliminated, the desired signal has a significant insufficient power, which can lead to the effect of quantization errors in fixed-point circuits. Quantization errors can lead to significantly higher bit error rates (BERs).

Disclosure of invention

Therefore, improved methods and apparatus for processing scenarios are needed in which significant differences are observed between known interference and desired signals. Such improved methods and devices should ideally contribute to the successful decoding of signals regardless of the current conditions in the cell. In particular, new solutions are needed to maintain cellular network performance in a low noise environment while suppressing high power interference.

In addition, it has been determined that appropriate enhancements are needed for existing hardware. Ideally, the implementation of the above improved methods and devices should not require significant changes to the currently available transceiver hardware or software. Imperfect behavior of hardware-related implementations should be taken into account during conversion, demodulation, signal processing, etc.

The present invention satisfies the above requirements by presenting, inter alia, improved methods and devices for controlling signal reception based on one or more network load estimates.

In a first aspect of the present invention, a method is disclosed for improving suppression in quantization of at least one signal among a plurality of signals and noise. In one embodiment, the plurality of signals comprises at least one other known signal, and the method includes: transmitting a plurality of signals; receiving information related to estimating network load based on the measured first attribute; and adjusting the transmission characteristics of at least one but not all of the signals from the plurality of signals based on said information.

In one embodiment, the first attribute comprises the ratio of the first network parameter to the second network parameter. The first network parameter contains, for example, the power of the common channel, and the second network parameter contains the total received signal. The network complies with the standard (or standards) of the Universal Mobile Telecommunications System (UMTS), and the common channel contains a common pilot channel (CPICH).

In another embodiment, the method comprises comparing the received information with at least one criterion; and at least in part based on a comparison result, selectively controlling transmission characteristics.

In a further embodiment, the step of adjusting transmission characteristics comprises signal amplification.

In yet another embodiment, the step of controlling transmission characteristics comprises reducing the order of the modulation group.

In another embodiment, the step of adjusting the transmission characteristics comprises a change in the transmission rate.

In yet another embodiment, the step of controlling transmission characteristics comprises changing one or more feedback parameters.

In a second aspect of the present invention, a method for improving the quantization characteristics of at least one radio signal among a plurality of radio signals is disclosed. In one embodiment, the method comprises: transmitting a plurality of radio signals, the transmission having a first radio attribute; receiving information related to the network load based on the first attribute; and adjusting transmission characteristics of at least one of the plurality of signals based on said information.

In one embodiment, the network complies with the standard (or standards) of the Universal Mobile Telecommunications System (UMTS), and the first radio attribute comprises a ratio of the power of a common channel to the total received signal.

In another embodiment, the formation step comprises: comparing the relationship with at least one threshold criterion; and at least in part based on a comparison result, selectively controlling transmission characteristics.

In yet another embodiment, the at least one radio signal is a dedicated channel.

In a further embodiment, the plurality of radio signals comprises at least one common signal, at least one unwanted signal, and at least one useful signal. In one embodiment, the step of adjusting transmission characteristics comprises amplifying at least one desired signal. In another embodiment, the step of controlling transmission characteristics comprises reducing the order of the modulation group of the at least one desired signal. In yet another embodiment, the step of adjusting the transmission characteristics comprises changing the transmission rate of at least one desired signal. In yet another embodiment, the step of controlling transmission characteristics comprises changing one or more feedback parameters of at least one desired signal.

In a third aspect of the invention, a wireless communication device is disclosed. In one embodiment, the wireless communication device comprises: a wireless communication interface configured to receive a plurality of signals; logic configured to determine network load; a processing device connected to the memory, and a computer program comprising a plurality of executable instructions stored in the memory. When executed by the processing device, the program: receives the first signal channel through a wireless communication interface; requests a second signal channel; Estimates network load transmits information related to network load estimation. One or more receiving characteristics of the second signal channel is determined by the specified information.

In one embodiment, the wireless communication interface has a plurality of fixed-point processing means, and the fixed-point processing means is a receiving characteristic determined by said information.

In another embodiment, the receiving characteristic is the target signal-to-noise ratio (SIR, signal to interference level).

In yet another embodiment, the receiving characteristic is determined in consultation with the serving device.

In yet another embodiment, the information related to the estimation of network load includes an indication of the power of the first signal channel compared to the power of the plurality of signals.

In a fourth aspect of the present invention, a service device is disclosed. In one embodiment, the device comprises a wireless communication interface configured to transmit and receive multiple signals; a processing device connected to the memory; and a computer program including many executable instructions in memory. When executed by a processing device, the program: receives a network load estimate through a wireless interface; performs responsive control of one or more transmission characteristics of at least one, but not all, of the plurality of signals.

In a fifth aspect of the invention, a method for compensating one or more orthogonal signals having a significantly higher transmit power than a user signal is disclosed. In one embodiment, the orthogonal signals result in a quantization error of the user signal, and the method comprises: obtaining a network load estimate; and responsively adjusting one or more transmission characteristics of the user signal, at least in part based on the network load, so that the regulation reduces the quantization error.

In one embodiment, one or more orthogonal signals comprise a pilot channel, and adjusting one or more transmission characteristics of the user signal comprises increasing transmit power of the user signal.

In a sixth aspect of the invention, a wireless communication system is disclosed. In one embodiment, the system comprises a base station and at least one user device (eg, a mobile terminal or UE), the system being configured to dynamically control quantization errors caused by the interference environment and system parameters by adjusting one or more channel characteristics .

Other features and advantages of the present invention may be immediately determined by those skilled in the art with reference to the accompanying drawings and a detailed description of exemplary embodiments below.

Brief Description of the Drawings

1 is a graphical illustration of one embodiment of a known UMTS network comprising a core network, a plurality of base stations, and a plurality of user terminals.

Figure 2 shows a graphical illustration of the known methods of automatic gain control (AGC) and analog-to-digital conversion (ADC) from the prior art, emphasizing the effects of correct and incorrect implementation of AGC and ADC.

Figure 3 shows a graphical representation of one approach for calculating the received signal strength (RSS, Received Signal Strength), applicable in relation to the calculation of the AGC in various embodiments of the invention.

Figure 4 shows a logical display of one example of an automatic gain control (AGC) feedback loop applicable to the present invention.

5 is a graphical representation of a signal structure enabling quantization noise reduction in accordance with an exemplary embodiment of the present invention.

FIG. 6 is a flow chart of an exemplary embodiment of a generalized process for improving signal reception based on one or more network load estimates in accordance with the present invention.

FIG. 7 is a flowchart illustrating one exemplary embodiment of the method of FIG. 6.

On Fig shows a block diagram of one embodiment of a generalized serving device made in accordance with the present invention.

Figure 9 shows a block diagram of one embodiment of a generalized receiving device made in accordance with the present invention.

10 shows a temporal and frequency representation of an Orthogonal Frequency Division Multiple Access (OFDMA) implementation applicable to various embodiments of the present invention.

The implementation of the invention

The following are references to the drawings, with all of them the same designations refer to the same parts. Overview The present invention provides, inter alia, methods and devices for controlling reception of signals based on one or more estimates of network load. In accordance with a further more detailed description, one exemplary implementation related to UMTS systems eliminates the effects of quantization errors inherent in a low noise and high noise environment. In particular, in a low noise environment, the common pilot channel (CPICH) of the UMTS system becomes the predominant factor in automatic gain control (AGC) calculations, resulting in the removal of the CPICH channel, the remaining dedicated physical channel (DPCH, Dedicated Physical Channel) twitches strong (harmful) effects of quantization.

Thus, in one aspect of the present invention, the receiver monitors network load and requests “enhanced” operation during periods of low network load. In one embodiment, during such periods of low network load, the receiver requests an increase in power levels for its data channels. For example, in one embodiment related to UMTS systems, the UE requests an increase in DPCH power levels when the observed ratio of the CPICH to the total power spectral density (CPICH / N ₀ ) exceeds a predetermined threshold. Large values of this relationship have a causal correlation with periods of low network utilization; total power spectral density includes power allocated to other users.

In general, various aspects of the present invention encompass a wide range of solutions both for monitoring network load and for regulating signal reception. For example, in one exemplary embodiment, a UMTS terminal (eg, a mobile device) is described that measures a CPICH / N ₀ ratio. Other alternative measurements include determining other resources, other transmitters, other receivers, and the like. Still other described embodiments are applicable to other network technologies and topologies. Similarly, the base station BS of the UMTS system that controls the power level of the DPCH channel with respect to the CPICH channel is also described. Additional variations and alternative embodiments are intended for various coding schemes, transmission rates, hardware operation, and the like.

A serving device and a wireless communication device suitable for implementing various other aspects of the present invention are also described. For example, in one embodiment, the UMTS NodeB serving node is configured to dynamically adjust the power levels of its DPCH and CPICH channels to counteract the expected effects of quantization errors. In yet another example, the UMTS NodeB serving node is configured to dynamically control modulation group order, transmission rate, and the like.

A receiving device is also disclosed. For example, one embodiment of the UMTS system UE terminal monitors and notifies the NodeB node of the UMTS system about network load conditions.

It also describes how to conduct business and modes of network optimization.

Detailed Description of Exemplary Embodiments

The following are exemplary embodiments of the present invention described in detail. Although these embodiments are mainly described in the context of a wireless network having a CDMA radio interface, and, in particular, its specific implementation of UMTS, it is obvious to a person skilled in the art that the present invention is in no way limited to said CDMA networks or any a specific context (such as the aforementioned particular UMTS embodiments). In fact, the principles of the present invention can be easily adapted for any wireless networks, and even non-cellular networks, in which network load is an undesirable interference level, thereby affecting the processing of the desired signal.

For example, it is understood that OFDMA-based systems (orthogonal frequency division multiple access) must decode the entire frequency band of a radio resource (including unwanted time-frequency resources) to successfully allocate the required time-frequency resources. Common implementations of OFDMA schemes utilize large Fast Fourier Transform (FFT) / Inverse Fast Fourier Transform (FFT) components to extract channels of interest. Since all time-frequency resources are converted at the same time, the signal is converted together for both required and undesirable time-frequency resources.

UMTS Network Architecture Example

In the following description, a cellular radio communication system is provided comprising a network of radio communication cells, each of which is served by a transmitting station, known as a cellular communication node or base station (BS). A radio communication network provides a wireless communication service for a plurality of user equipment transceivers (UEs). A network of co-operating BS stations is provided for a wireless communication service having more coverage than the radio coverage provided by one serving BS. Separate BSs are connected by another network (in many cases a wired network), which contains additional controllers for resource management and, in some cases, access to other network systems (such as the Internet or MAN (regional network)).

In a UMTS system, the base station is usually called “NodeB”. The UMTS Terrestrial Radio Access Network (UTRAN) is a common set of NodeB nodes together with the UMTS Radio Network Controllers (RNCs). The user accesses the UTRAN via the UE, which in many typical use cases is a cell phone or smartphone. However, the terms “UE”, “client device” and “end user device” as used herein may include, but are not limited to, cell phones, smartphones (such as, for example, iPhone ™), personal computers (PCs) with wireless capabilities such such as iMac ™, Mac Pro ™, Mac Mini ™ or MacWook ™, and minicomputers such as desktops, laptops or others, as well as mobile devices such as PDAs, PDAs, wireless personal media devices (PMDs, personal media device), such as, for example, iPod ™, or any combo above the nation.

FIG. 1 shows an example of a UMTS cellular system 100 with focus on a radio access network (RAN).

System 100 comprises one or more towers 102 of base stations (also known as NodeB (NB) nodes) that are installed in various fixed geographic locations. Such NodeB nodes may also be generally referred to as “macro cells”. Each NodeB provides a service coverage area 104.

The network operator controls the operation of the access radio network through the core network 106. A single core network provides authentication, calculation and authorization services (AAA, authentication, accounting, and authorization), and in some cases access to external networks (such as IP multimedia subsystem services (IMS, IP Multimedia Subsystems), as indicated by the 3GPP group). The first terminal UE 108 is shown operating within the coverage of the RAN 100 network.

In addition, emerging wireless standards support new network entities, commonly referred to as “femtocells”; femtocells provide the functionality of macrocells, however, they have reduced capabilities and cost and can be made portable as opposed to stationary. Femtocells can be purchased by users for personal use. The combination of macrocells and femtocells ensures a unified unified service from a network operator. Within the UMTS network, femtocells are generally designated as NodeB home nodes 112 (HNB, Home IModeB) and have a corresponding coverage area 114.

Each of the cells (where macrocells and femtocells are represented) is directly connected to the core network 106, for example, via broadband access. In addition, in some networks, cells can be coordinated with each other through secondary access. In the RAN 100 network shown in FIG. 1, femtocells are connected to a core network, but are not connected to other network cells. In contrast to the broader coverage of macrocells, femtocells are mainly focused on improving the service of multiple users. Accordingly, femtocells may have settings and restrictions that are not applicable to the general population. Such custom installations are typically described, at least in part, in publicly available pilot channel broadcasts. Therefore, macrocells and femtocells can have different pilot channel powers, loads, and operation.

While the following description is presented in terms of downlink from NodeB 102 to terminal UE 108, it is obvious that similar processes and structures can be easily applied within the uplink (from UE to NodeB) by a person skilled in the art, if any the contents of the present description.

Common pilot channel (CPICH) and dedicated physical channel (DPCH)

The UMTS network uses a common pilot channel (CPICH) to provide all user terminals (UEs) with a common synchronization signal. In general, pilot channels are used, among other things, for initial “waking up” and searching, evaluating the reception service of a potential base station (BS) for handover (i.e., switching between stations), etc. Various approaches are known in the art for organizing pilot channels. For example, in Interim Standard 95 (IS-95, CDMA), pilot channel measurements are used by mobile devices to initially determine the presence of base stations and / or to provide multipath compensation.

The importance of the CPICCH channel for network management and network discovery is justified by the disproportionate share of the transmission resources of the NodeB 102 node. In extreme cases, the transmission power of the CPICCH channel of the UMTS system can reach one fifth (20%) of the total transmission power of NodeB. The high CPICH power ensures that the terminal 108 within the coverage area 104 (even at the very edge) can receive synchronization information. In summary, the common “control” channels are the most reliable (stable) channels with the simplest encoding in the network.

UMTS networks also provide dedicated physical channels (DPCH) to provide channels for transmitting control messages (DPCCH, Dedicated Physical Control Channel, dedicated physical control channel) and data (DPDCH, Dedicated Physical Data Channel, dedicated physical data channel) for individual terminals UE 108. In contrast to CP1CH, a DPCH is received by only one UE receiver. Non-destination UE terminals cannot decode other DPCH channels. However, the exclusivity of DPCHs still affects the overall network performance. Each additional DPCH increases interference to all non-receiver terminals. Therefore, the network operators as a whole maximize the functionality of the system by limiting the power of the DPCH channels to the minimum necessary to communicate with the desired terminal UE.

Power Management in UMTS

Terminals UE 108 and NodeB 102 interact with each other to control DPCH channel power using both open and closed power control loops (closed loop). The target quality levels of DPCH signals are set and dynamically controlled according to the available radio conditions. For example, in a radio environment with significant noise, the NodeB increases the transmit power of the DPS to improve reception of the UE. In an environment with less noise, DPCH transmit power is reduced. Dedicated Physical Channel Power Management (DPCH) is divided into two (2) circuits: (i) an external power control loop and (ii) an internal power control loop.

An external power control loop performs power control with respect to long-term changes in the radio environment. The UE 108 and the NodeB 102 host negotiate and control the SIR (Signal to Interference Ratio) within the Radio Resource Connection (RRC) protocol. The SIR ratio allows you to predict the value of the proportion of errors in the block (BLER, block error ratio); for example, if the received SIR is less than the target SIR ratio, then the BLER is generally bad. UEs and NodeB set a target SIR based on the BLER share of the reference physical channel (DPCH). The reference physical channel may have one or more transport channels. The transport channel, which requires the lowest error rate in the block to obtain satisfactory quality, is the reference for the target SIR. The transport channel BLER is the number of bit errors in a block or frame after channel decoding and error correction.

The internal power control loop (also known as a closed loop power control loop with a high reaction rate) is configured to protect against short-term fading. The internal control loop uses the same target values set by the control of the external loop (i.e. derived from analysis performed after processing); however, the control is based on a physical radio connection (PHY level) and can respond faster to compensate for short-term fading, etc.

In the operation of the UMTS in accordance with the prior art, the target SIR is determined after the gain carried out after processing (orthogonal interference components are excluded and spreading gain is applied, etc.); the target SIR is based only on the received DPCH signal power with respect to the actual noise. For example, in one embodiment, the DPCH SIR ratio is measured based on the pilot field transmitted on the DPCH. This pilot signal has a known structure. The UE may estimate the DPCH signal strength by averaging the signal strength in the pilot field in accordance with the following expression (1);

$$S=I^2+Q^2,\left(\mathrm{one}\right)$$

where S is the signal power, I is the value of the in-phase components, Q is the value of the quadrature components.

In addition, the CPICH channel noise can be estimated from the variance of these pilot fields or measured from CPICH in accordance with the following expression (2):

$$N_{CPICH}=\mathrm{var}\left(m\mathrm{about}un\mathrm{about}\mathrm{from}tbCIPCH\right).\left(2\right)$$

The noise affecting the CPICH channel is common to all orthogonal channels. Accordingly, after measuring the noise using the CPICH, the processed noise visible by the DPCH can be derived from N _CPICH based on the difference in the spreading factors (SF, Spreading Factor) (or processing gains). For example, N _DPCH can be calculated using the following expression (3):

$$N_{DPCH}=\left(S{F}_{DPCH}/S{F}_{CPICH}\right)*N_{CPICH},\left(3\right)$$

where N _DPCH - noise channel DPCH; SF _DPCH — DPCH channel spread factor; SF _CPICH — CPICH channel spread coefficient; NC _PICH - CPICH channel noise.

Accordingly, the SIR ratio of the DPCH can now be expressed in accordance with the following expression (4):

$$SI{R}_{DPCH}=S/N_{DPCH}.\left(\mathrm{four}\right)$$

Automatic gain control (AGC)

In addition to power control, conventional UMTS receivers 108 also perform various forms of signal processing, including automatic gain control (AGC). In conventional transceiver designs, an automatic gain control (AGC) module amplifies or attenuates the overall received signal in order to maintain the relative constant signal for digital processing by the receiver in the main frequency band. In contrast to power control, AGC is carried out regardless of signal quality; in fact, AGC is performed in conjunction with analog-to-digital conversion (ADC).

Turning now to FIG. 2, various stages 200 of signal conversion can be seen presented to emphasize the effect of the correct and incorrect functioning of the AGC and ADC. Consider the received analog signal 202. The signal consists of several components: (i) constant bias 204, (ii) high- and low-frequency noise 206 and in-band component 208. The radio frequency part can remove both the constant bias and undesirable frequency components at the initial stage ( or stages) of filtration. The in-band component 208 is transferred to the main frequency band, for example, by mixing and filtering the carrier frequency.

After the desired frequency components 208 are transferred to the main frequency band, the radio frequency part must amplify or attenuate the signal for digitalization so that the necessary digital processing can be performed. The radio frequency part is usually performed using fixed-point calculations. In contrast, floating point calculations deal with numbers having a mantissa and exponent. Calculations with a fixed comma can be complementary (optional), etc., taking into account the sign, without taking into account the sign. Ideally, the entire dynamic range of the converted analog signal can be represented completely in analog-to-digital fixed-point conversion. Fixed-point operations have a fixed range, for example a word of eight (8) fixed-point bits can only display 256 numbers (i.e., 2 ⁸ = 256). Therefore, to minimize the effect of quantization errors, it is necessary to carefully select a quantum (quantization element) or a minimal element.

The first and second digital representations (210, 212 in FIG. 2) of the analog oscillation illustrate the effect of excessive gain and / or too small a quantum value in different implementations. The first fixed-point view 210 has difficulty displaying peaks and lower vibration points; these artifacts saturate the fixed-point analog-to-digital conversion components, causing distortion or “clipping” effects.

The second fixed-point view 212 illustrates various phenomena that may also be common to various receiver embodiments. Instead of “trimming” the excessively amplified signal, the second fixed-point representation “overlaps”, creating false artifacts in the signal display. Overlapping or looping is caused by an incorrect overflow operation; for example, consider unsigned fixed point calculations for four (4) bits. With a maximum value of # 1111b (31), the number # 10000b (32) cannot be processed; therefore, the value is truncated to # 0000b (0).

Obviously, both the first and second views 210, 212 are undesirable. In contrast to the first and second views, the third fixed-point view 214 of the analog waveform illustrates the effect of a lack of gain or a too large quantum. Although the third view does not create any “artifacts,” the wobble cannot be fully represented. Therefore, a quantization error (i.e., the difference between the real analog value and the quantized digital value) directly causes a false interpretation of the symbol and reduces the effective bit rate (i.e. due to a higher BER).

Finally, the fourth analogue fixed-point representation 216 of the oscillation in FIG. 2 illustrates a correctly amplified oscillation. The fourth representation can capture the entire dynamic range of the analog waveform, while at the same time providing sufficient clarity to prevent bit errors in demodulation and processing operations. In some embodiments, a small cut or indent may be acceptable or even preferable (for example, for more reliable signal capture, fade compensation, packet transmission, etc.).

In the preceding description, it is quite obvious that the relative complexity and sensitivity of radio communications significantly affects the requirements for the choice of fixed-point ADC components. Simple radio signals in a low noise environment, etc. may be supported by lower-resolution fixed-point components. Similarly, complex signals and / or noisy environments require higher bit resolution. For example, it is not unusual for CDMA receivers to use ADC components with a resolution of eight (8) or even ten (10) bits. A resolution of eight (8) bits can display up to 256 (i.e. ^2-8 ) different gradation levels. A resolution of ten (10) bits can display up to 1024 (i.e. 2 ¹⁰ ) different gradation levels.

Conventional AGC implementations use RSSI (Received Signal Strength Indication) to control changes in the radio environment in a simple feedback loop. FIG. 3 is a graphical representation of one example RSSI measurement 300. RSSI is calculated as the value (or some derivative thereof) of the in-phase and quadrature components of the received signal. FIG. 4 shows one example of a simple feedback loop 400 implementing an AGC based on RSSI (such as that obtained using the approach shown in FIG. 3). As shown, RSSI 402 is calculated, 404 is multiplied by a constant, and is used as feedback to amplify the incoming signal 406. In other embodiments, comparisons between current energy estimator and the like may be used.

The AGC coefficient is dynamically adjusted to correctly capture the entire signal range. For example, if RSSI increases, the gain decreases. If RSSI goes down, the gain goes up.

Functional scenario example

Now, with reference to one example scenario (shown in FIG. 5), operation of one terminal UE in the vicinity of a relatively unoccupied NodeB station is described. It should be recalled that the received signal contains at least the desired or “useful” channel 502 (DPCH), orthogonal or “ignored” channels 504 (for example, CPICH, signals for other users of the same cell, etc.) and noise 506 (e.g., thermal noise, interference from cells, etc.).

In the exemplary scenario of FIG. 5, CPICH 502A dominates other elements (e.g., DPCH 506A, noise 504A, and the like). Unfortunately, after the removal of the CPICCH channel, the relatively low-power DPCH channel undergoes large quantization errors. Thus, as previously described, the fixed-point hardware used in conventional wireless communication devices cannot display the entire signal with the accuracy necessary to separate the useful and ignored parts of the received signal included in the above scenario.

In this regard, one aspect of the present invention leads to the regulation of target resources by the wireless communication device and / or base station based on estimates of network load. In one exemplary embodiment, the ratio of the CP1CH channel to the total received signal is used to estimate the network load, although it is obvious that other network load metrics can easily be used instead of (or in conjunction with) the above approach.

In particular, in an exemplary embodiment, the ratio E _C / M _{0 of} the CPICCH channel (also referred to as CPICH / N ₀ ) measures the power (E _C ) allocated to the CPICCH channel with respect to the total spectral density of the received power (N ₀ ; also denoted I ₀ ). The total spectral density of the received power contains both the required signals and unwanted interference signals in the form as they are measured on the connecting element of the antenna of the mobile station. For example, a high CPICH / N ₀ ratio indicates that the NodeB node clearly transmitted the CPICCH channel in a relatively silent environment; thus, in the cell (obviously) many other DPCH channels are not supported.

The above estimation of network load is used in one implementation for dynamic regulation of “safe indentation”, and the regulation process is adapted to reduce quantization errors. In particular, a larger margin of safety is used when the CPICH / N ₀ power ratio is high (for example, above -7 dB); less safety margin is used when the CPICH / N ₀ power ratio is low (for example, below -7 dB). Obviously, although a two-level model is described (i.e., above or below -7 dB), if necessary, any number of different levels and / or logical hierarchies can be used in accordance with the present invention. For example, a three-level model can be used, having two different secure boundaries and two thresholds.

When the first threshold is reached, the first safe indentation is implemented, and if the second threshold is reached, the second safe indentation is implemented.

When the exemplary receiver embodiment notifies the NodeB that a high CPICH / N _{0 has} been determined, NodeB accordingly enhances the transmit power of the corresponding DPCH using safe indent. For example, an increase in DPCH transmit power by 25% is sufficient to eliminate quantization errors in UMTS networks with little or no noise.

An “increase” in transmit power affects the internal power control loop. In particular, in this example, the NodeB node raises its target SIR value. Since the NodeB must correspond to a high SIR for the UE, the power for the DPCH allocated to the UE is increased. In this example case, the normal operation of the internal power control loop has the task of achieving a target SIR of 0 dB. During the corrective operation, the internal power control loop has the task of achieving a target SIR of 1 dB (approximately 25% increase in transmit power based on doubling the power to increase every 3 dB). The internal power control loop in the illustrated implementation may change at a frequency of once every 0.66 ms; thus, a certain amount of hysteresis is also provided to prevent unnecessary clutter or catch of the target SIR (i.e., when CPICH / N ₀ falls below -7 dB, the improved target SIR is still valid for a short transition hysteresis period). As shown, CPICH 552 still prevails over other elements; however, the power of the DPCH 556 is increased compared to the noise of the 554.

For lightly loaded cells, the increased transmit power of the DPCH 506B is not affected. If there is no other equipment in the cell, the NodeB can focus on increasing DPCH power to reduce quantization errors, thereby improving call quality of the receiver. Upon entering the cell of additional user equipment, the effect of the quantization error decreases (as the noise increases), as a result of which NodeB can reduce the safe indentation, returning to normal operation (i.e., without quantization adjustment).

The preceding example is illustrative only and other embodiments and options are described in more detail below.

For example, alternative systems can measure / accept other indicators, use more complex regulatory boundaries or implementation criteria, observe other conditional events, etc.

In addition, while the previous examples are limited by the CDMA (Code Division Multiple Access) standard based on the UMTS cellular network, it is obvious that the invention can be widely applied by specialists in the relevant fields of technology in other systems based on the contents of the present description. For example, other multiple access schemes are possible, such as OFDMA (orthogonal frequency division multiple access), TDMA (Time Division Multiple Access, time division multiple access), FDMA (Frequency Division Multiple Access, frequency division multiple access) and other systems based on CDMA, each of which has analog elements.

Similarly, other CDMA-based schemes (e.g., IS-95, CDMA-2000, etc.) may use other indicators (e.g., pilot channels, synchronization channels, etc.) to estimate network load and control quantization errors.

Ways

Next, with reference to FIG. 6, one embodiment of a generalized intelligent quantization indentation procedure for regulating signal reception based on one or more network load estimates is described. The functional elements described in connection with the method 600 of FIG. 6 are a client device (eg, a mobile device, UE, or other user device) and a serving device. In addition, the communication line includes at least: (i) one or more desired or “useful” signals, (ii) one or more unwanted or “ignored” interference signals, and (iii) noise.

At 602, one or more indicators related to network load are measured. In one embodiment, indicators are measured in a client device. For example, in the previously described operational example (see “An example of a functioning scenario”), the client device measures the ratio of the power of the common pilot channel (CPICH) to the power of the total received signal (N ₀ ). Obviously, such quantities are system dependent; they can also be easily replaced with other quantities. It should also be noted that conventional names may vary in different technologies (for example, N ₀ may be equivalent to RSS (received signal strength), I ₀ , etc.). In alternative embodiments, indicators are measured in a serving device.

In one implementation of the invention, the above indicators comprise power measurements of one or more unwanted signals. For example, unwanted signals may contain at least one sounding signal. In one such embodiment, the pilot channel power is measured. As previously noted, the CPICCH channel is usually excluded during signal processing. Similarly, “unwanted” signals may contain other pilot channels, synchronization channels, common channels, control channels, dedicated channels for other users, etc.

In step 604 of method 600 of FIG. 6, network load is assumed or estimated based on one or more of the indicators from step 602 (or a combination thereof). In one embodiment, one or more indicators (or a combination thereof) is compared with one or more acceptance or action criteria (eg, threshold levels). One exemplary implementation uses a single threshold value, as described previously; above the threshold, the network is considered lightly loaded, while below the threshold, the network is considered normal or heavily loaded. In the previously described operation example (see “Example operation scenario” described previously), the client device compares CPICH / N ₀ with a set threshold (-7 dB). However, as previously noted, additional gradation scales may be applied; for example, many other thresholds can be set over the entire range of operation. Empirically measured CPICH / N ₀ ratios can range from -2.5 dB to -24 dB. For example, in fixed-point circuits, thresholds set with an increase of 3 dB (for example, -5 dB, -8 dB, -11 dB, -14 dB, -17 dB and -20 dB) can easily be implemented.

In alternative embodiments, the estimated network load is determined in a deterministic manner based on one or more indicators (as opposed to a simple yes / no threshold). For example, the estimated network load can vary linearly, exponentially, logarithmically, etc., and this functional relation can be used to calculate the actual load value in connection with the indicator (for example, CPICH / N ₀ ).

In some embodiments, the estimated network load (or an indicator useful for calculating it) is reported to the serving device, while the transmitting device (eg, UE) makes the actual determination. Alternatively, the estimated network load (or the constituent components necessary for performing the calculation) can be calculated at the receiving (eg, serving) device. In yet another embodiment, the network load may be estimated by a third party (for example, a relay device, a master base station, a third party object or server connected to a network, or the like). For example, some technologies use other base stations to monitor and control network performance. One such example, typical of UMTS, involves the interaction between serving or leading base stations and non-serving base stations. Future cellular networks (e.g. LTE (Long Term Evolution)) may contain various forms of base stations, including substantially limited base stations (e.g. microcells, femtocells, picocells, etc.). Such base stations with limited functionality may receive some information useful for determining network load (for example, some indicators of radio resources available for use, etc.).

As yet another implementation, two or more devices or objects may cooperate in a “distributed” manner, for example, when the UE performs some calculations or data preprocessing and then sends the preprocessed data to a server (or other object) to complete the processing. This approach can virtually save uplink bandwidth, however, by increasing the processing costs (and power consumption) of the client.

At step 606, the serving device adjusts the signal transmission based on the estimated or estimated network load. In one exemplary embodiment, the power level of one or more desired or “useful” signals is increased. For example, in the previously described example, the DPCH is amplified by increasing the target SIR (signal-to-noise ratio) of the connection and radio resources (RRC). A higher target SIR directly translates into a stronger desired signal (DPCH) compared to other unwanted signals (eg, containing noise).

Several other methods may also be presented to improve the reception of useful signals. For example, in one embodiment, the channel coding of one or more desired or “useful” signals may be dynamically adjusted. As you can easily understand, different modulation groups are more or less sensitive to quantization errors. For example, binary phase shift keying (BPSK, Binary Phase Shift Keying) is less sensitive to quantization errors than quadrature phase shift keying (QPSK, Quadrature Phase Shift Keying). Similarly, various higher-order modulation groups, for example, 16-QAM, 64-QAM, 256-QAM (Quadrature Amplitude Modulation, quadrature amplitude modulation), etc. are prone to quantization errors with an increase compared to small-order modulation groups. Accordingly, higher order modulation groups are used only for low noise environments. Consequently, higher order modulation groups can further consider the “best part” of the range in which (i) each symbol can be easily distinguished from noise and (ii) each symbol can be fully displayed in available fixed-point hardware. For example, a compromise can be achieved between the use of modulation groups with high orders and large target SIRs, or, conversely, between a decrease in the order of a modulation group and maintaining (or even reducing) a target SIR.

In other embodiments, additional hardware elements may be activated or deactivated. In one such embodiment, the receiver connects auxiliary fixed point expanding hardware during periods with a high probability of quantization errors. For example, during normal operation, fixed point calculations are set to eight (8) bits. During appropriate situations, additional expansion hardware is included that supports fixed point calculations with ten (10), twelve (12) bits, etc. In yet another embodiment, the transmitter and receiver may connect special modulation or bit rate hardware.

In addition, it should be noted that the symbols of the modulation group are highly sensitive to quantization errors, while the transmission rate is not. Since the speed of the raw data is a combination of the complexity of the modulation group and the transmission speed, it is obvious that a compromise between these two factors can affect the operation of the serving device. For example, the serving device may determine that the desired signal should be transmitted using the same modulation group at the same speed but at increased power. Alternatively, the serving device may switch to a higher transmission rate using a modulation group with lower complexity in order to conserve transmission power. Other options are described in more detail below (see “Example of a base station, Example of a mobile device”, presented below).

With reference to FIG. 7, one embodiment of the generic method of FIG. 6 is illustrated to improve signal reception based on one or more network load estimates 700. At step 702, CPICH and N ₀ are measured. The ratio of E _C / N ₀ channel SRIC has a high correlation with the load on the network node NodeB. If the CPICH / N ₀ reaches -7 dB, then the mobile device accepts that NodeB operates with very little network load. In contrast, if CPICH / N _{0 is} lower than -7 dB, then the mobile device assumes that NodeB is operating at normal network load.

An example receiver notifies NodeB that the network load seems too small; those. that quantization errors can affect the quality of service (QoS, Quality of Service) (704). NodeB responds with one or more adjustment options. For example, as shown, in step 706, the NodeB node sets the target SIR to a higher minimum value (1 dB).

Since NodeB must correspond to a higher SIR level for the UE, NodeB increases the power of the DPCH channel with respect to the CPICCH channel (708).

In alternative embodiments, the NodeB may configure other parameters to reduce quantization noise recorded by the receiver. For example, other embodiments may choose between increasing the target SIR, changing the transmission rate, changing the order of the modulation group, and the like.

Base Station Example

Next, with reference to Fig. 8, an example of a base station 800 implementing the previously described functionality is illustrated and described. The base station 800 of the illustrated embodiment is basically presented as a separate device for use in a cellular network, however, other form factors for execution may also be provided (e.g., femtocells, picocells, access points, mobile access points, components in other main devices, etc. .).

The device of FIG. 8 comprises one or more circuit boards 802, which further comprise a plurality of integrated circuits, including a processing subsystem 804 such as a digital signal processor (DSP), a microprocessor, a programmable logic device or logic array, or a plurality of processing components, a radio frequency transceiver (s), and a power management subsystem 806 that provides power to a base station 800.

Processing subsystem 804 comprises, in one embodiment, an internal cache or multiple processors (or a multi-core processor). The processing subsystem 804 is preferably connected to a memory subsystem 808, which may comprise static random access memory, flash memory, synchronous dynamic random access memory, and the like. The memory subsystem may implement one or more types of hardware with direct memory access to facilitate fast data access.

An example device 800 in some embodiments implements some form of broadband access 810 to a core network object and / or access 812 to another device 600. For example, broadband access can be provided with a DSL connection (ie, through a DSL subsystem), although instead DSL subsystems can use other interfaces, wired or wireless. One of skill in the art can understand that the DSL interface can be easily replaced or shared with other broadband access schemes, such as a DOCSIS cable modem, T1 line, WiMAX (i.e., IEEE 802.16 standard), ISDN, FiOS, microwave line, satellite line, etc.

Base station 800 also includes one or more subsystems of the radio modem. The modem subsystems 814 give the base station the ability to provide service for one or more subscriber units. Obviously, in some implementations of the invention, many subsystems may be required. For example, a base station may provide a plurality of subsystems of a radio modem to provide, among others, operation in multiple modes (eg, GSM, GPRS, UMTS, and LTE) in many different radio interfaces. The modem subsystem 814 comprises a modem, an RF portion, and one or more antennas.

It should also be noted that in some embodiments, it may be necessary to eliminate some of the elements currently shown (such as the radio frequency part) or, alternatively, the discrete elements shown may be combined with each other as a single component.

As previously described, implementations of a base station of the invention generate signals for a communication link with one or more receiving devices; The communication line is composed of a number of signals. Besides. at least one or more desired or “useful” signals are routed to one or more receivers. The invention allows the base station to additionally generate signals that are undesirable or "ignored" for at least one or more receiving devices.

In one exemplary embodiment, the UMTS NodeB base station 800 generates a common pilot channel (CPICH) 552 to provide all user terminals (UEs) with a common synchronization signal. The NodeB base station also generates dedicated physical channels (DPCH) 556 for transmitting control messages (dedicated physical control channel (DPCCH)) and data (dedicated physical data channel (DPDCH)) to individual terminals UE. Each DPCH is received by only one receiving terminal of the UE.

An example NodeB UMTS base station 800 is further configured to receive one or more indicators associated with estimated or calculated network load. As previously described, the NodeB UMTS station is configured to generate or receive CPICH / N ₀ measurements, which are CPICCH power measurements relative to the total received signal power. It is obvious that the above indicators can be easily replaced by a specialist in the art with similar indicators of the previously described type based on the contents of the present description.

In one aspect of the present invention, the NodeB 800 can dynamically adjust the modulation characteristics of the DPCH 556 to reduce the impact and / or the likelihood of quantization errors. In one exemplary embodiment, the regulation causes an increase in DPCH transmit power when the indicators associated with the network load estimation / determination exceed one or more threshold values. In alternative embodiments, the DPCH transmit power may be calculated by an algorithm in order to provide linear, exponential, logarithmic, or the like regulation. progression.

In addition, as previously indicated, other alternative embodiments may improve the suppression of quantization errors. Quantization errors affect different aspects of channel coding in different ways. Each of the transmission power, antenna configurations, such as modulation grouping, channel coding complexity, auxiliary hardware operation, and the like. has a different degree of exposure to quantization errors. Thus, in one embodiment, the base station intelligently considers channel coding methods that suppress both noise and quantization errors, for example, through a computer program or other computerized logic that implements these functions.

Various channel coding methods are more or less susceptible to quantization errors. For example, quantization errors can have a very large influence on the type of modulation grouping; for comparison, the transmission rate is more independent of quantization errors. Thus, in another aspect of the invention, module operating rules related to methods for reducing quantization errors described herein are provided. This module comprises, in an exemplary embodiment, a sequence of software procedures or other hardware / software / hardware environments adapted to perform channel coding based on one or more operational representations.

For example, the rules implemented by the rule module can be codified as a sequence of preferences or a logical hierarchy (for example, changes in transmission power are preferable to changes in transmission speed; changes in a modulation group are preferable to changes in transmission power, etc.). In addition, the rule module may consider additional operational aspects beyond the quality of channel coding; for example, other aspects may include elements such as quality of service (QoS), subscriber credentials, business considerations, etc.

Other options for the functioning of the base station, containing channel coding implementations and rules module parameters, can easily be performed by a person skilled in the art based on the present description.

Mobile device example

Next, with reference to Fig.9 shows an example of a client device 900 (for example, a UE) that implements the methods of the present invention.

The UE device 900 includes a processing subsystem 904, such as a digital signal processor, a microprocessor, a user programmable gate array (FPGA), or multiple processing components mounted on one or more of the cards 902. The processing subsystem may also include an internal cache. The processing subsystem 904 is connected to a memory subsystem 908 comprising a storage device, which may comprise, for example, components of a static random access memory, flash memory, synchronous dynamic random access memory. The memory subsystem may comprise one or more types of direct memory access hardware to facilitate access to data, as is known in the art.

The radio / modem subsystem 910 comprises a digital baseband module, an analog baseband module, a transmitting part and a receiving part. The device 900 further comprises a set of antennas for receiving services from one or more base stations 800. Although a specific architecture is discussed, in some embodiments, some components can be eliminated or connected to each other (for example, a combination of a radio frequency receiving part, a radio frequency transmitting part, and ABB, type used for the radio frequency parts 3G), as this may be obvious to a person skilled in the art based on the present description.

The power management subsystem (PMS) 906 shown provides power for a UE terminal and may comprise an integrated circuit or a plurality of discrete electrical components. In one example of a portable UE device, the power management subsystem 906 advantageously has an interface with a battery.

The user interface system 912 includes any number of well-known I / O, including, but not limited to: a keyboard, touch screen, LCD, backlight, speakers, and a microphone. However, it should be understood that in some implementations one or more of these components may be absent. For example, UE equipment such as a PCMCIA card may not have a user interface (since it may be tied to the user interface of the device with which they are physically and / or electrically connected).

The device 900 may further comprise optional peripheral devices including, but not limited to, one or more GPS transceivers or network interfaces such as IrDA, Bluetooth ports, WLAN and / or WiMAX transceivers, USB, FireWire, etc. However, you must understand that these components are not required for the operation of the UE terminal in accordance with the principles of the present invention.

In the illustrated embodiment, the modem subsystem 910 further comprises subsystems or modules for receiving communication link signals generated by one or more serving device 800; moreover, the communication lines contain many signals. In addition, the modem subsystem is configured to extract (physically through filters or logically through computational operations) at least one or more desired or “useful” signals from unwanted signals.

In one exemplary UMTS implementation, a mobile device 900 (UE) is configured to receive one or more DPCHs (dedicated physical channels) 556 mixed with a common pilot channel (CPICH) 552. An exemplary UMTS system 900 UE is further configured to calculate and report one or more indicators related to estimated network load. As previously described, the terminal UE is configured to measure CPICH / N ₀ , which reflects a CPICH power measurement with respect to the power of the total received signal. As in the base station, the above indicators can be easily replaced by similar indicators by a person skilled in the art based on the contents of the present description.

The CPICH / N ₀ ratio determines the power allocated to the CPICCH channel (E _C ) relative to the total received power spectral density (N ₀ ). CPICH / N _{0 is} typically measured by the UMTS receiver for a handover / handoff operation (CPICH / N _{0 is} monitored for each base station in the active state for efficient cell selection). In an exemplary UE 900, CPICH / N ₀ is measured at a CDMA receiver configured to search for and correlate code words. In one embodiment, one or more conditional events (for example, determining an unusually high CPICH / N ₀ ) triggers a message to be sent to the corresponding serving device 800. After the example terminal UE 900 sends one or more indicators to the serving device 800 (base station), the serving device changes the characteristics of the DPCH (for example, the power allocated to DPS, etc.) to improve the suppression of quantization errors.

Alternative embodiments of the UE 900 can directly activate or deactivate internal hardware, thereby improving the suppression of quantization errors. For example, in one such embodiment, the receiver may have auxiliary fixed-point expansion hardware that is activated only during periods of high probability of quantization errors. During normal operation, fixed point calculations are set to eight (8) bits, and the optional extended logic circuitry is held in a reset state.

When launched in an appropriate situation, additional expansion hardware can be removed from the reset to support fixed point calculations with ten (10), twelve (12) bits, etc. Other variations of this circuitry can simply turn off the power to the expansion hardware, further improving power consumption when not in use.

For example, one embodiment of stackable hardware uses ADC components with a large number of fixed-point bits. During normal operation, the extra least significant bits (LSB, least significant bit) or the most significant bits (MSB, most significant bit) are ignored. After providing hardware expansion, the extra bits go into extended logic, providing additional granularity to reduce quantization errors.

Based on the present description, other variants of a mobile device can be easily implemented by a person skilled in the art.

OFDMA Networks

Consider an OFDMA (orthogonal frequency division multiple access) circuit 1000 in FIG. 10, in which the entire frequency band is divided into subcarriers 1002, which are further divided into time slots (timeslots) 1004; each combination of a time slot and a subcarrier is a time-frequency resource 1006. Each receiver is allocated a number of time-frequency resources. Conventional implementations of OFDMA receivers and transmitters use Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (FFT). Each receiver must perform FFT in the entire frequency band of radio resources (including unwanted time-frequency resources) to extract the required time-frequency resources. The transmitter should transmit with sufficient power to ensure that the receiver has substantially reliable information to extract the required time-frequency resources.

In those scenarios where different time-frequency resources have different power levels, more powerful time-frequency resources will prevail in FFT or IFFT operations. Thus, in some scenarios, low-power components of the time-frequency resources may not have sufficient reliability for successful extraction.

For example, during normal operation, a base station that transmits downstream OFDM signals to a number of receivers must dynamically adjust the transmit power of each subcarrier in order to compensate for effects such as short-term fading inherent in each receiver, etc. Unfortunately, as previously noted, each receiver demodulates all frequency resources using FFT. Consequently, closely spaced devices will receive signals in which the transmission power of undesired time-frequency resources prevails. More specifically, when converting time-domain data to a frequency domain in order to divide the carrier into component subcarriers, the subcarriers assigned to nearby receivers are relatively small compared to subcarriers that are amplified due to the effect of short-term fading.

Thus, in accordance with various aspects of the present invention, the OFDMA base station can use the minimum safe indent for near receivers. The minimum safe indentation ensures that each recipient can demodulate time-frequency resources without quantization errors.

Similarly, during normal operation, a base station that receives uplink OFDM signals from a number of receivers may require nearby mobile devices to gradually reduce their transmit power, and for further mobile devices to gradually increase transmit power. However, the base station still needs to receive a signal of sufficient quality from nearby devices to avoid quantization errors. Thus, in this example, the BS may require nearby devices to increase the uplink power by a safe margin to eliminate quantization errors.

Functional / Business Rules Module

The degree of tolerance for quantization suppression for a base station may directly depend on various required characteristics for the subscriber; however, the solution in accordance with the invention sometimes functions through other network operations. For example, increasing the transmit power of the DPCH improves reception by the first subscriber, but also adversely affects neighboring subscribers. Thus, in another aspect of the invention, a business rule module is provided relating to a quantization error avoidance apparatus and methods described herein. This module comprises, in one exemplary embodiment, a sequence of software procedures or other relevant hardware / software elements adapted to control the operation of the previously described quantization error suppression.

In fact, the business rule module contains a controlling object that monitors and selectively controls the functions of managing and avoiding business overloads (for example, income, profit and / or QoS level) in order to implement the required business rules. The rule module can be considered as an add-on over the algorithms of basic control / avoidance of quantization errors. For example, the above invention is well suited to provide high data rates in relatively simple reception conditions. Thus, in one such model, a service provider / network operator can provide an improved non-quantization data service for users wishing to pay a premium as an incentive for high-level users or even paid by another third party.

Some business models may offer such useful features embodied in premium equipment. For example, femtocells of home use may support such preferred services. In other models, the network operator may provide different levels of quantization resistance. For example, all high data rate UE terminals can be grouped into a first class, and lower data rate UE terminals can be grouped into a second class. The service can be provided for both the first and second class of UEs, and the terminals of the UEs of the second class have different stability (for example, higher CPICH / N ₀ thresholds, etc.).

In yet another aspect of the present invention, it is apparent that the above solution can be used to connect devices with lesser capabilities. For example, a device having a fixed-point resolution of only six (6) bits can be used with a relatively clean channel. In UMTS networks, such devices may always require more DPCH power. The consequences of limited operations for low-cost, low-capacity devices can have useful business applications. Thus, if the present description is available, those skilled in the art can determine that less costly implementation options can be implemented having fixed-point calculations with fewer characters. However, such designs should still reliably distinguish each character in noise; however, a greater susceptibility to quantization errors of such structures can be overcome by increasing transmission power.

Obviously, although certain aspects of the invention are described in terms of specific process steps, these descriptions are merely illustrations of a more general method in accordance with the invention and can be modified if necessary for private use. Certain steps may be considered optional or optional under certain circumstances. In addition, certain steps or functionalities may be added to the described embodiments, or the order of two or more steps may be changed. All such variations are considered to be within the scope of the invention described and presented in the claims.

While the above detailed description shows, describes and emphasizes the new features of the invention used in various embodiments, it should be understood that various exceptions, replacements and changes in the form and details of the illustrated device or process can be made by a person skilled in the art without deviations from the invention. The above description is the best implementation of the present invention, presented at the present time. This description is in no way intended to be limiting and should be considered as an illustration of the basic principles of the invention. The scope of protection of the invention should be determined with reference to the claims.

Claims (26)

1. A method of reducing quantization errors of at least one signal among a plurality of signals and noise, the method comprising:
transmission of multiple signals;
receiving information related to estimating network load based on power measurements;
determining a desired amount of transmission power adjustment of at least one but not all signals from the plurality of signals based on comparing said information with one or more threshold values, wherein each of one or more threshold values corresponds to a transmission power adjustment amount; and
adjusting the transmission characteristics of at least one, but not all of the signals from the plurality of signals by a value thus determined. 2. The method according to claim 1, characterized in that the power measurements comprise the ratio of the first network parameter to the second network parameter. 3. The method according to claim 2, characterized in that the first network parameter contains the power of the common channel, and the second network parameter contains the total received signal. 4. The method according to claim 3, characterized in that the network complies with the standard (s) of the Universal Mobile Telecommunication System (UMTS), and the common channel contains a common pilot channel (CPICH). 5. The method according to claim 2, characterized in that it further comprises: comparing the received information with at least one criterion; and at least in part based on a comparison result, selectively controlling transmission characteristics. 6. The method according to claim 1, characterized in that the step of regulating the characteristics of the transmission contains signal amplification. 7. The method according to claim 1, characterized in that the step of regulating the transmission characteristics comprises reducing the order of the modulation group. 8. The method according to claim 1, characterized in that the step of regulating the transmission characteristics comprises changing the transmission speed. 9. The method according to claim 1, characterized in that the step of regulating the transmission characteristics comprises changing one or more feedback parameters. 10. A method for improving the quantization characteristics of at least one radio signal among a plurality of radio signals, the method comprising:
transmitting multiple radio signals, the transmission having power measurements;
receiving information related to network load based on power measurements;
determining a desired amount of transmission power adjustment of at least one but not all signals from the plurality of signals based on comparing said information with one or more threshold values, wherein each of one or more threshold values corresponds to a transmission power adjustment amount; and
adjusting the transmission characteristics of at least one of the plurality of signals by a value thus determined. 11. The method according to claim 10, characterized in that the network complies with the standard (s) of the Universal Mobile Telecommunication System (UMTS), and the power measurements comprise the ratio of the power of the common channel to the total received signal. 12. The method according to claim 11, characterized in that the step of forming comprises: comparing the relationship with at least one threshold criterion; and at least in part based on a comparison result, selectively controlling transmission characteristics. 13. The method according to claim 11, characterized in that at least one radio signal is a dedicated channel. 14. The method according to claim 10, characterized in that the plurality of radio signals comprises at least one common signal, at least one unwanted signal, and at least one useful signal. 15. The method according to 14, characterized in that the step of regulating the transmission characteristics comprises amplification of at least one useful signal. 16. The method according to 14, characterized in that the step of regulating the transmission characteristics comprises reducing the order of the modulation group of at least one useful signal. 17. The method according to 14, characterized in that the step of regulating the transmission characteristics comprises changing the transmission speed of at least one useful signal. 18. The method according to 14, characterized in that the step of regulating the transmission characteristics comprises changing one or more feedback parameters of at least one useful signal. 19. A service device containing
a wireless communication interface configured to transmit and receive multiple signals;
a processing device for exchanging data with memory; and
a computer program that includes many executable instructions in memory, which when executed by a processing device:
receives an estimate of network load through a wireless interface;
performs responsive control of one or more transmission powers of at least one, but not all of the signals from the plurality of signals by an amount obtained based on the estimated network load. 20. A wireless communication device comprising
a wireless communication interface configured to receive a plurality of signals;
logic configured to determine network load;
a processing device connected to the memory; and
a computer program that includes many executable instructions in memory, which when executed by a processing device:
receives a first signal channel through a wireless interface;
requests a second signal channel;
Estimates network load
transmits information related to the assessment of network load,
moreover, the transmitted information provides an indication of the direct magnitude of the desired power adjustment of the second signal channel in order to reduce quantization errors. 21. The device according to claim 20, characterized in that the wireless communication interface has a plurality of fixed-point processing means, and the fixed-point processing means is a receiving characteristic determined by said information. 22. The device according to claim 20, characterized in that the receiving characteristic is the target level of the signal-to-noise ratio (SIR). 23. The device according to claim 20, characterized in that the receiving characteristic is determined in coordination with the serving device. 24. The device according to claim 20, characterized in that the information related to the assessment of network load, contains an indication of the power of the first signal channel in comparison with the power of many signals. 25. A method of compensating for one or more orthogonal signals having a significantly higher transmit power than the user signal, and leading to a quantization error of the user signal, the method comprising:
getting an estimate of network load; and
responsive control of one or more user signal transmit powers by an amount obtained at least in part based on network load, so that control reduces the quantization error. 26. The method of claim 25, wherein the one or more orthogonal signals comprise a pilot channel, and adjusting one or more transmission characteristics of the user signal comprises increasing the transmit power of the user signal.

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